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91.
Priv.-Doz. Dr. Claus -Peter Schnorr 《Probability Theory and Related Fields》1970,15(4):313-328
Summary We continue the discussion on the definition of random sequences from Part I. We will show that the idea of Kolmogoroff to characterize random sequences by their program complexity can be formulated in such a way as to let this definition coÏncide with the others given in Part I. Another equivalent definition of random sequences can be derived from the games of chance. A sequence is random, if and only if no player who calculates his pool by effective methods can raise his fortune indefinitely when playing on this sequence. Finally we will study transformations which preserve the random property of a sequence. We will prove that the original concept of v. Mises can also be modified in such a manner as to coÏncide with all our other definitions. A sequence is random, if and only if it satisfies the strong law of large numbers and if every sequence obtained from it by a constructive measure-preserving transformation is random, too.
Die Arbeit stellt einen Teil der Habilitationsschrift dar, die der Mathematisch-Naturwissenschaftlichen FakultÄt der UniversitÄt des Saarlandes vom Verfasser vorgelegt wurde. 相似文献
Die Arbeit stellt einen Teil der Habilitationsschrift dar, die der Mathematisch-Naturwissenschaftlichen FakultÄt der UniversitÄt des Saarlandes vom Verfasser vorgelegt wurde. 相似文献
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95.
Robert E. Linder Günter Barth Edward Bunnenberg Carl Djerassi Lloyd Seamans Albert Moscowitz 《Chemical physics letters》1974,28(4):490-493
The MCD spectrum of formaldehyde in the vapor phase has been measured and analyzed. Triplet bands occur with unusually high ellipticity, allowing identification of several new singlet-triplet bands. Also, an additional singlet progression, based on two quanta of the out-of-plane band and a single quantum of the antisymmetric CH stretch, has been identified. 相似文献
96.
Helen?BarbasEmail author Claus?C?Hilgetag Subhash?Saha Caterina?R?Dermon Joanna?L?Suski 《BMC neuroscience》2005,6(1):32
Background
The neocortical commissures have a fundamental role in functional integration across the cerebral hemispheres. We investigated whether commissural projections in prefrontal cortices are organized according to the same or different rules as those within the same hemisphere, by quantitatively comparing density, topography, and laminar origin of contralateral and ipsilateral projections, labeled after unilateral injection of retrograde tracers in prefrontal areas. 相似文献97.
Florian?Nettesheim Claus?B.?Müller Ulf?Olsson Walter?RichteringEmail author 《Colloid and polymer science》2004,282(8):918-926
We report on the shear induced transition from the L3- to the L-phase studied by means of flow birefringence using the system pentaethyleneglycol monododecylether (C12E5), decane, water. The dependence of the critical shear rate, at which the transition from the isotropic state to the anisotropic takes place, on membrane volume fraction was studied in temperature ramp experiments at different constant shear rates and in isothermal shear ramp experiments. These results are compared with relaxation experiments from the shear aligned state back to the isotropic. For all these experiments power law exponents in the membrane volume fraction between 1.6 and 2.8 were found, which are rather low compared to values of current theories. The values found for the inverse critical shear rate and the decay times from the relaxation experiments differ by four orders of magnitude. 相似文献
98.
A theoretical analysis of an optical fiber photonic-bandgap-based refractometer is presented. The design is based on a quarter-wave reflector with one defect. By modifying both the real and the imaginary parts of the index of refraction of the defects we begin to change either the frequency or the amplitude of the localized optical mode. So we could fabricate a specific optical fiber refractometer by combining all the variables: index of refractive index of the defects and the rest of layers, thickness of the defect, number of layers, etc. to yield a large set of design possibilities, for example, detecting wider or thinner ranges of refractive indices, or controlling the detection accuracy. Some rules for the practical implementation of the refractometer are given. 相似文献
99.
Jacob C Giles GI Giles NM Sies H 《Angewandte Chemie (International ed. in English)》2003,42(39):4742-4758
Sulfur and selenium occur in proteins as constituents of the amino acids cysteine, methionine, selenocysteine, and selenomethionine. Recent research underscores that these amino acids are truly exceptional. Their redox activity under physiological conditions allows an amazing variety of posttranslational protein modifications, metal free redox pathways, and unusual chalcogen redox states that increasingly attract the attention of biological chemists. Unlike any other amino acid, the "redox chameleon" cysteine can participate in several distinct redox pathways, including exchange and radical reactions, as well as atom-, electron-, and hydride-transfer reactions. It occurs in various oxidation states in the human body, each of which exhibits distinctive chemical properties (e.g. redox activity, metal binding) and biological activity. The position of selenium in the periodic table between the metals and the nonmetals makes selenoproteins ideal catalysts for many biological redox transformations. It is therefore apparent that the chalcogen amino acids cysteine, methionine, selenocysteine, and selenomethionine exhibit a unique biological chemistry that is the source of exciting research opportunities. 相似文献
100.
Self-assembled microarrays of attoliter molecular vessels 总被引:1,自引:0,他引:1
Stamou D Duschl C Delamarche E Vogel H 《Angewandte Chemie (International ed. in English)》2003,42(45):5580-5583